Zipaquirá, Colombia

This underground Roman Catholic church in Zipaquirá may be a stunning architectural marvel, but at 101,551 residents, the city is hardly a tranquil backwater. Bureaucracy is a persistent headache, with the original cathedral being forced to shut down in 1992 due to "structural problems and safety concerns." While the new cathedral is an impressive feat, the constant influx of 3,000 Sunday visitors means this place is better suited for tourists than those seeking a quiet life.